Hello and welcome.
My name is ***** ***** I will be glad to help with your question.
TSA Precheck uses a randomized system of selection to determine which passengers will get the service on each flight. There is no guarantee that you will get Precheck every time you fly. What might help, is to call all the airlines you use and/or on which you are frequent flyer, and make sure they have your KTN (Known Traveler Number) and are a TSA Pre passenger, and have them add that to your profile; this will increase your chances of getting Precheck on future flights.
If you're not flying out for a few hours, you might even try calling your airline now, and ask that the Precheck be added, then they can send you another boarding pass or you can pick it up when you get to the airport.
I know it's frustrating and disappointing, because you went through the process of enrolling in and paying for Precheck, but no one ever mentioned to you that it's randomized for purposes of enhancing security and you might not get it on every flight.
This is a list of other reasons why you might not have gotten Precheck on this flight:
You can call the phone number listed at the link above, to get more information, if needed.
I wish you a great flight, today!
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